"Vicious" marks the first time the two legendary British actors have done a TV sitcom.

The British sitcom from “Will and Grace” writer Gary Janetti, premieres on ITV this month.

CANNES – As the issue of gay marriage dominates the headlines worldwide -- from decisions by the U.S. Supreme Court on Proposition 8 to pro- and anti-gay marriage protests on the streets of Paris -- the release of new British sitcom Vicious could not seem better timed.

The show, which bows on Brit commercial network ITV later this month, stars British acting giants Ian McKellen and Derek Jacobi as a bickering gay couple who have been together for decades.

“It's strictly coincidence that this issue is happening in the world,” says Gary Janetti, the U.S. writer who created Vicious. “But I think whenever the issue of gay marriage comes up the first couples that get married are these people that have been together 50 years, and you see these two women and these two men in their 80s. And I defy anybody not to be moved by that.”

Gary Reich, the managing director of Brown Eyed Boy, which is producing the show together with fellow Shine Group shingle Kudos Film, admits the timing of Vicious is particularly prescient. During the taping of the second episode in the six-part first season earlier this year, the British Parliament -- located directly across the Thames river from ITV's studios -- were voting to give same sex couples in Britain equal status under the law.

“They passed the law while we were filming,” says Reich. “We got the news to the actors and Ian and Derrick announced it to the studio audience: 'While we are doing this show, across the river they just changed the law.'”

Janetti, who received multiple Emmy nominations as a writer and producer of Will and Grace, thinks Vicious also breaks new ground similar to the way NBC's hit sitcom did more than a decade ago.

“It does have a certain resonance because this is the first time we are seeing a gay couple on TV that have been together for 48 years when the show starts. We haven't seen a relationship like this on TV before,” Janetti says. “I think Will and Grace helped change attitudes, as did things in pop culture like The Real World putting gay characters in those households... it always works when there is no political agenda involved, where you are just entertaining. This is part of the fabric of the world, there's nothing more complicated than that."

Vicious certainly isn't aiming for a niche audience. “It's a big, loud, traditional multi-camera network show” says Janetti. ITV, Britain's biggest commercial network, is putting the show out in primetime. Australia's Seven Network, which has a similarly wide commercial appeal, just picked up Vicious from Shine Group for local release.

For both McKellen and Jacobi, who have been friends since university and are both openly gay, Vicious is groundbreaking in another way. The show marks the first time the two acclaimed actors -- McKellen's credits include the X-Men and The Hobbit while Jacobi appeared in such films as Gladiator (2000) and The King's Speech (2010) -- have acted together. Vicious is also, aside from Jacobi's single, Emmy-winning, guest appearance on Frasier in 2001, the first time either of them has performed in a TV sitcom.

“Neither of them had ever done a multi-camera sitcom,” says Janetti “but its very theatrical. Doing a multi-camera sitcom in front of an audience is very much like live theater. And when you have such extraordinary theater actors and you are doing a comedy, my feeling is you have to put them in front of an audience".

Vicious also features Iwan Rheon -- who appears as Ramsay Snow in the third season of HBO's Game of Thrones – and veteran British actress Frances de la Tour (Rising Damp). The show hasn't yet been sold to the U.S., but inspired by the success of Downton Abbey, Janetti sees no obstacles for this very British show to hop the pond.

“The world has become smaller, Downton Abbey is the biggest hit PBS has every had, in my lifetime at least,” he says. “We all know what a British accent sounds like – we all watched Absolutely Fabulous – I think American audiences will go for this show and will watch it in its British form."